List of publications

Anza M, Haile E, Tadesse S, Mammo F, Endale M (2014)

Objective: To isolate and characterize chemical constituents of the roots of Zanthoxylum chalybeum (Z. chalybeum). Methods: A number of phytochemical tests were applied to identify the class of compounds present in the CH2 Cl2 /CH3 OH (1:1) root extract. Column chromatographic separation technique was applied to separate the constituents of the CH2 Cl2 /CH3 OH (1:1) root extract and various spectroscopic techniques [UV-vis, infrared radiation, nuclear magnetic resonance (NMR) (1 H- NMR, 13 C NMR, DEPT-135, COSY, gHSQC and gHMBC)] were used to determine the structures of pure compounds. Results: Phytochemical screening of the CH2 Cl2/CH3OH (1:1) root extract of Z. chalybeum revealed the presence of alkaloids, flavonoids, terpenoids, tannins and anthraquinones. Column chromatographic separation of the extract yielded a new coniferyl alcohol derivative, 2, 3-epoxy- 6,7-methylenedioxyconiferyl alcohol (1) together with the known alkaloid, dihydrochelerythrine (2). Conclusions: The present work conducted on the CH2 Cl2:CH3OH (1:1) root extract of Z. chalybeum identified various class of compounds present in the root extract. Complete characterization of two compounds were done using spectroscopic techniques of which a coniferyl alcohol derivative (1) was identified for the first time.

Abstract Question How well does the forest classification system of the 1:5,000,000 vegetation map of Africa developed by Frank White correspond with classification systems and more extensive information on species assemblages of higher resolution maps developed for Ethiopia, Kenya, Malawi, Rwanda, Tanzania, Uganda and Zambia? Methods We reviewed various national and sub-national vegetation maps for their potential in increasing the resolution of the African map. Associated documentation was consulted to compile species assemblages, and to identify indicator species, for national forest vegetation types. Indicator species were identified for each regional forest type by selecting those species that, among all the species listed for the same phytochorion (regional centre of endemism), were listed only for that forest type. For each of the national forest types, we counted the number of indicator species of the anticipated regional type. Floristic relationships (expressed by four different ecological distance measures) among national forest types were investigated based on distance-based redundancy analysis, permutational multivariate analysis of variance (PERMANOVA) using distance matrices and hierarchical clustering. Results For most of the national forests, the analysis of indicator species and floristic relationships confirmed the regional classification system for the majority of national forest types, including the allocation to different phytochoria. Permutation tests confirmed allocation of national forest types to regional typologies, although the number of possible permutations limited inferences for the Zambezian and Lake Victoria phytochoria. Two forest types from Ethiopia and Kenya did not correspond to regional forest types. Conclusions Our analysis provides support that as the classification systems are compatible, the resolution and information content of the vegetation map of Africa can be directly improved by adding information from national maps, probably leading to improved liability of its application domains. We found statistical evidence for a distinct Afromontane phytochorion. We suggest expanding the regional forest classification system with ‘Afromontane moist transitional forest’. Among the various application domains of the higher resolution maps, these maps allow for an enhanced phytochoristic analysis of eastern Africa.

Weinsheimer F, Mengistu A, Rödder D (2010)

Ethiopia harbours 9 species of threatened amphibians, all of which inhabit the high- lands. Over the last decades, there has been a rapid increase in deforestation and habitat degrada- tion in Ethiopia, with the result that the last undisturbed refuges for forest-dwelling anurans in the mountain areas have shrunk noticeably, especially outside of protected areas. In the present study, we used a maximum entropy ecological niche modelling approach to model the potential distribution of 2 poorly known Leptopelis species. The models were derived from climate and land cover data at known occurrences of the species (i.e. data from a number of natural history museums). These mod- els can be used to select the priority areas most critical for future protection and may guide further field surveys to accelerate the discovery of unknown populations.